Apologies for not replying sooner Michael. It's very difficult to tell anything for sure from your photos. However, it certainly looks like there is some mold or damp affecting your ceiling. To make sure I'd recommend an affordable, scientifically-proven mold test kit which you can buy online such as these EC3 Test Plates from Micro Balance Health Products. They're easy to use if you follow the enclosed instructions. Alternatively, if you're living in rented accommodation then you should alert your landlord immediately (if you haven't already) as mold is a serious threat to health. To take it further you would be looking at having an environmental health inspector look at the issue and your property as a whole. Whatever your situation, please do make sure to at least test for mold yourself with a proven kit or get a professional in. Mold is not something you can ignore in any circumstance!
All the best.
If you are going through hell, keep going - Winston Churchill
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